Before the start of business, Just Security provides a curated summary of up-to-the-minute developments at home and abroad. Here’s today’s news.

SYRIA

President Trump yesterday dialed down his rhetoric on U.S. action in Syria, earlier in the week, the President warned Russia to “get ready” for U.S. military strikes on Syria, but has now taken a more measured tone in response to last Saturday’s alleged chemical weapons attack in the Syrian town of Douma. Anne Gearan, John Wagner and Missy Ryan report at the Washington Post.

Defense Secretary Jim Mattis also took a more cautious approach when discussing military options in Syria, telling the House Armed Services Committee yesterday that Trump has not yet made a decision on what response to take to the Douma attack. Ellen Mitchell reports at the Hill.

“We have proof that … chemical weapons were used, at least with chlorine, and that they were used by the regime of [Syrian President] Bashar al-Assad,” the French President Emmanuel Macron said yesterday, adding that “we will need to take decision in due course, when we judge it most useful and effective.” France24 reports.

Samples from the Douma attack have tested positive for chemical weapons, according to two U.S. officials familiar with intelligence collected by U.S. or foreign assets on the ground, adding that they were “confident” but not 100 percent sure about the information gathered. Courtney Kube and Ken Dilanian report at NBC News.

Inspectors from the Organization for the Prohibition of Chemical Weapons (O.P.C.W.) expect to begin a fact-finding mission in Douma on Saturday, the Syrian government has said that it would facilitate the investigation. Bassem Mroue and Sarah El Deeb report at the AP.

The British Prime Minister Theresa May’s cabinet have agreed “on the need to take action” in Syria, according to Downing Street, with ministers saying it was “highly likely” that Assad’s forces were responsible for the alleged chemical weapons attack in Douma. The BBC reports.

Trump and May agreed in a phone call yesterday that “it was vital that the use of chemical weapons did not go unchallenged, and on the need to deter the further use of weapons by the Assad regime,” according to a Downing Street statement, which came after the Prime Minister’s cabinet gave their backing for joint action with the U.S. and France against Assad’s government. Reuters reports.

“The immediate priority is to avert the danger of war [between the United States and Russia],” the U.N. ambassador to Russia Vassily Nebenzia told reporters yesterday after a private Security Council meeting, adding that he “cannot exclude” the possibility of a conflict should the U.S. and its allies take military action against Assad. The BBC reports.

“Iran will stand by Syria under any circumstances,” a top adviser to Supreme Leader Ayatollah Ali Khamenei, Ali Akbar Velayati, said yesterday after meeting with Assad, according to the Iranian Irna state news agency. Saeed Kamali Dehghan reports at the Guardian.

Trump’s military advisers have warned that a miscalculated military response to Syria could risk an escalation with Russia and Iran, who are both key supporters of Assad. Kevin Liptak and Jennifer Hansler report at CNN.

“We cannot depend on the mood in which someone wakes up out there across the ocean, and what comes into the head of a certain person in the morning,” the Russian Deputy Prime Minister Arkady Dvorkovich told the Russian R.I.A. Novosti state news agency today, referring to Trump’s conflicting Twitter messages on Syria. Henry Foy reports at the Financial Times.

President Trump has authority to carry out to attack Syria based on the 2001 authorization for the use of military force (A.U.M.F.), the House Speaker Paul Ryan (R-Wis.) said yesterday, however the House Minority Leader Nancy Pelosi (D-Calif.) disagreed with this assessment and said a new A.U.M.F. was needed. Mike Lillis reports at the Hill.

The U.N. Security Council has scheduled another emergency meeting today following a request by Russia, which included a call for a briefing by the Secretary-General António Guterres. The AP reports.

An explanation of the “deconfliction” hotline between the U.S. and Russia in Syria, and its relevance to any possible U.S.-led military strikes, is provided by Patrick Wintour at the Guardian.

Trump must now forge a coherent strategy, the president has so far relied on mixed messages that have muddled the U.S. approach to Syria. David Ignatius writes at the Washington Post.

“The goal now, in an extremely difficult situation, should be for the U.S. to formulate a response that acts as a deterrent,” the Wall Street Journal editorial board writes, arguing that a symbolic, limited strike would be ineffective and that President Trump should shape a strategy that “the world will recognize as a sustained commitment” to deterring Russia, Iran and Assad.

U.S.-led airstrikes continue. U.S. and coalition forces carried out nine airstrikes against Islamic State targets in Syria and Iraq between March 30 and April 5. [Central Command]

POMPEO CONFIRMATION HEARING

The C.I.A. Director Mike Pompeo faced the Senate Foreign Relations Committee as part of the process to confirm him as Trump’s new Secretary of State, during his testimony Pompeo sought to present himself as in favor of strong diplomacy and well-suited to improving morale at the State Department. Michael R. Gordon and Nancy A. Youssef report at the Wall Street Journal.

Pompeo said he hoped for a diplomatic solution to the crisis on the Korean Peninsula, that he wanted to “fix” the 2015 Iran nuclear deal and that he would take a tough line against Russia. Patricia Zengerle and Lesley Wroughton report at Reuters.

Pompeo confirmed in the hearing that a “couple hundred Russians” were killed in Syria in February, saying that this demonstrated the Trump administration’s tough approach to Russia. Rebecca Kheel reports at the Hill.

The President and his administration intend to ensure that North Korea irreversibly dismantles its nuclear arsenal, Pompeo said yesterday, adding that there would be no “rewards” from talks with the U.S. until Pyongyang takes steps towards denuclearization. David Brunnstrom and Patricia Zengerle report at Reuters.

Pompeo faced tough questions from lawmakers, including on the investigation into Russian election interference. Despite skepticism expressed by some lawmakers, the Senate is widely expected to confirm him as Secretary of State, Robbie Gramer reports at Foreign Policy.

Pompeo’s tone and demeanor contrasted starkly to his approach to the 2015 hearings on Benghazi, when he was a lawmaker. Gardiner Harris and Eileen Sullivan report at the New York Times.

Pompeo did not change the minds of many Democrats who asked what strategy he would be advocating on key foreign policy issues and expressed concerns about Pompeo’s approach to diplomacy. Elana Schor and Nahal Toosi report at POLITICO.

Pompeo should be confirmed immediately, while there are legitimate concerns about his views, it is important that Trump receives counsel during a time of multiple foreign policy crises. The Washington Post editorial board.

TRUMP-RUSSIA

The White House has been formulating talking points to undermine the Deputy Attorney General Rod Rosenstein –who oversees special counsel Robert Mueller’s Russia investigation – according to sources familiar with the matter, with the White House wanting allies to highlight Rosenstein’s role as a key witness in the firing of former F.B.I. Director James Comey. Sara Murray, Kevin Liptak and Pamela Brown report at CNN.

The prospect of an interview between Mueller and Trump has dimmed. According to multiple sources familiar with the matter, Mueller’s office and Trump’s legal team are continuing their strategies on the basis that an interview will not take place, Carol E. Lee, Julia Ainsley, Kristen Welker and Hallie Jackson report at NBC News.

Comey’s new memoir is expected to be released Tuesday and includes details of his interactions with Trump and their discussion of the dossier compiled by British Intelligence officer Christopher Steele, which alleged connections between the Trump campaign and Russia. Michael D. Shear reports at the New York Times.

A breakdown of seven eye-catching claims made in Comey’s book are provided by Cristiano Lima at POLITICO.

A bipartisan bill to protect Mueller may be jeopardized by partisan infighting between the Chairman of the Senate Judiciary Committee Chuck Grassley (R-Iowa) and the top Democrat on the panel, Dianne Feinstein (D-Calif.). Burgess Everett reports at POLITICO.

CYBERSECURITY, PRIVACY AND TECHNOLOGY

The Facebook C.E.O. and founder Mark Zuckerberg answered hundreds of questions over two days of congressional hearings about the social media firm and privacy, which came amid the scandal surrounding the political research firm Cambridge Analytica and their harvesting of data from Facebook. However key questions remain about Facebook’s approach to privacy, Alyssa Newcomb reports at NBC News.

The Cambridge Analytica contractor Aleksandr Kogan collected direct messages from Facebook users without their permission and in breach of their privacy. Alex Hern and Carole Cadwalladr report at the Guardian.

Zuckerberg did not address the misuse of Facebook outside North America and Western Europe, the social media platform has been used to stir misinformation and hatred in countries such as Burma, Vietnam and Sri Lanka. Adam Taylor writes at the Washington Post.

OTHER DEVELOPMENTS

The Chinese Navy staged its largest ever parade of Navy vessels in the South China Sea yesterday, the drills were overseen by President Xi Jinping and come at a time of increased tensions in the waters, and between the U.S. and China. Ben Westcott, Steven Jiang and Serenitie Wang report at CNN.

At least 13 policeman were killed by Taliban militants in locations across Afghanistan last night, the AP reports.

The al-Qaeda-linked al-Shabaab group claimed responsibility for a bomb explosion at a stadium in northern Somalia yesterday, which killed five people and injured several others. Abdi Guled reports at the AP.